Re: Batteries

Nov 21, 2016 1 Replies
A


On Monday, October 10, 2016 at 11:06:50 AM UTC-4, Phil Hobbs wrote:-


>
> Torque is proportional to current, no?
> -
> Yep. But a DC motor dead-stopped is a short circuit. And even a very
> nearly crapped-out battery may have enough to blow a fuse if
> dead-shorted. Fuse action is not voltage dependent (as long as the fuse
> is rated at a higher voltage than the application).
>
> Peter Wieck
> Melrose Park, PA

Hi...i am a new user here. As per my knowledge the bad batteries caused the electronic controller to draw too much current in an attempt to maintain speed.That's just a guess, though. It is hard disagnose something with no information.

AlfySande
Vote
Twitter Facebook LinkedIn
P

I think you left out a step:

a) The batteries ran low. b) The user kept 'upping' control to maintain speed. c) As long as the motor is turning, things are (mostly) OK. d) The motor (brush-type) stops dead, but the speed control is still on MAX. e) Now the full - remaining - battery capacity is going through the fuse. f) *POOF*

But, the batteries are sulphated, the speed controller has been overheated, the motor overheated - or at least those commutator contacts arced. Altogether a mess.

Any properly designed system would have a condition meter and a low-battery cut-off to prevent this. And a thermal breaker in addition to the fuse.

Peter Wieck Melrose Park, PA

Vote
Twitter Facebook LinkedIn

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required